Getting Started With Analysis

Citizen Sky is now officially permanent part of the AAVSO. In the coming weeks we will be moving additional content to the AAVSO site and freezing this site as an archive of the 1st three years of the project. Please visit the new landing page for future updates.

One of the components that makes this citizen science project unique is its focus on data analysis. Participants aren't asked to simply to collect data for scientists to analyse, but they can do the analysis themselves. This includes steps such as identifying a project/problem/goal, collecting data, performing quality control procedures on it, analysing it and communicating results to others.

The first stage of the project, until Fall of 2010, will be focused more on the data collection aspect and background information on the project. We will begin building out the data analysis section around the beginning of 2010.

5 Star Analysis Tutorial: This 5-Star Analysis Tutorial is meant to introduce you to basic ways of data processing and inspection. It does not assume a background in astrophysics, statistics or anything similar. However, all good researchers need to understand what their data actually mean. So if you have never made a variable star estimate before, we strongly recommend first reading our 10-Star Observing Tutorial. That will give you an idea of where these data come from and what it means to actually observe a variable star.

VStar: VStar is a new java-based, open-source software package in development for use by Citizen Sky participants. Volunteers are needed to help write code, documentation and to test the software. Visit the team page for more information.

We are also working on tutorials in the following areas:

How to validate data: How to differentiate between valid observations and observations that are not useful for analysis. This will include tools for making your own validation of the observations submitted by other people so you can create your own custom data set and/or you will be able to share your validation decisions with others.

Basic statistics for light curves: This will include tutorials about building mean curves, folding data taken across many cycles to make it look like it's one cycle (i.e. building phase diagrams) and understanding standard deviation and other descriptions of error and uncertainty. An introduction to light curves tutorial is already online.

Advanced time series analysis: Time series data is that which is taken over a set amount of time. In this case, we have observations taken of a star over a long period of time. There are a number of powerful statistical tools that can be used to analyse such data. Usually they involve searching for periodicity (recurrent cycles) in the data and/or changes in any periodicity. Some of the tools we'll provide training on include Fourier analysis, wavelet analysis and ANOVA techniques. An introduction to time series analysis is already online here.